The polishing amount of an optical fiber component is typically measured by inserting a tip portion of the optical fiber component into a ferrule, polishing with a polishing machine such as disclosed in Patent Literature 1 and 2, and estimating the measured polishing amount of the ferrule as the polishing amount of the optical fiber component.
FIG. 7 is an explanatory drawing illustrating the polishing of an optical fiber component 1 inserted into a ferrule 15. The optical fiber component is obtained, for example, by welding an end cap 13 to the tip of an optical fiber 10. The left side of FIG. 7 illustrates a state before the polishing in which the ferrule tip is aligned with the tip of the optical fiber component 1 (tip of the end cap 13). Where the polishing is performed as depicted on the right side of FIG. 7, the measured polishing amount g of the ferrule is taken as the polishing amount of the optical fiber component 1. The reference numeral 12 in the figure stands for a coating of the optical fiber 10.